Elevating-truck.



G. E. CLARK.

ELEVATING TRUCK. APPLICATION FILED FEB. 24. 1914.

1,174,685., Patented Mar. 7,1916.

4 SHEETS-SHEET I.

ATTORNEY.

e. E. CLARK. ELEVATING TRUCK.

APPLICATION FILED FEB. 24, IBM-- Patented Mar. 7,1916;

4 SHEETS-SHEET 2.

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WIfNESSES:

G. E. (ELARK.

ELEVATING TRUCK.

APPLICATION FILED FEB. 24. 1914.

4 SHEETS-SHEET 3- WITNESSES: 11v VEN TOR '4 wgyeflhm. I BY 2 ATTORNEY.

Patented Mar. 7, 1916.

G. E. CLARK.

ELEVATING TRUCK.

APPLICATION FILED FEB. 24. 1914.

1,174,685, Patented Mar. 7, 1916.

WITNESSES.-

' INVENTOR.

A TTOR NEY.

UNITED STATES PATENT OFFICE.

GEORGE E. CLARK, OF WINDSOR LOCKS, CONNECTICUT, ASSIGNOR TO GEORGE I.CLARK COMPANY, OF WINDSOR LOCKS, CONNECTICUT, A CORPORATION OFCONNECTICUT.

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Specification of Letters Patent.

Application filed February 24, 1914. Serial No. 820,541.

county of Hartford and State of Connecti cut, have invented certain newand useful Improvements in Elevating Trucks, of which the-following is aspecification.

This invention relates to an improved elevating or lifting truck. Thetruck which is known-in the art as an elevating truck or lifting truckis shown generally by such a patent as that to Gledhill, #790,495, May23. 1905.

The object of the invention is to provide in such a truck improvedmeansconnected with the handle of the truck for operating the elevatingmechanism.

Another object of the invention is to pro vide in such a truck improvedmeans to operate the elevating mechanism by the handle, said meansconstructed and arranged Another object of the invention is to pro videa cable connection between the handle and the elevating mechanism havinga universal joint connection with the handle to operate the elevatingmechanism, by the movement of the handle.

Another object of the invention is to provide an improved means forlooking the platform of the truck in elevated position in a positivemanner.

Another object of the invention is to provide, in a truck of the classmentioned, improved mechanism combined with the means for locking theplatform in elevated position operable to conveniently release the lookwhen desired.

v Another object of the invention is to pro-- 'vide in combination withthe means for locking the platform in elevated position,

an improved safety device which will pre- .vent accident from a carelessrelease of the lock or careless or accidental lowering of the wide alock for the platform in elevated position which is automaticallyreleased by .manipulating the handle, together with a safety, deviceoperable to lock the platform in elevated position, when the operatorfails to lower the platform in a careful manner.

Other objects of the invention will appear in the detailed descriptionand annexed claims.

For the purpose of illustrating one preferred embodiment or one mannerof carrying out my invention, reference is had to the accompanyingdrawings in which:

Figure 1 is a side elevational view of a truck embodying my invention,with the rear portion broken away and indicating the platform in loweredposition. Fig. l is a side elevation of the rear portion of the trucknot shown in Fig. 1, a small part however, being shown in both figures.Fig. 2 is a plan view of the assembled truck, certain parts being brokenaway to better show the elevating mechanism thereunder. Fig. 3 is avertical longitudinal-sectional view through the front half of the truckwith the rear portion broken away, showing the elevating mechanism insome detail, with the platform in raised position. Fig. 3 is a verticallongitudinal sectional view of the rear portion of the truck not shownin Fig.

3, a small part,'however, being shown in both figures. Fig. 4 is asectional view taken on the line 44 of Fig. 5. Fig. 5 is a frontelevation detail view of the platform lock. Fig. 6 is a verticalelevation showing a detail of the elevating mechanism. Fig. 7 is asectional view taken on the line 7-7 of Fig. 6. Fig. 8 is a sectionalview taken on comprises a main frame 3 mounted on two wheels at the rearand one wheel suitably swiveled at the front. At each of the fourcorners of the main frame there is provided an eccentric gear pivotallymounted and arranged to engage the teeth of a rack 8, mounted at thefour corners of the superimposed platform 4. These four gears are eachprovided with a cam '15 '(see Fig. 8), which may be integral with-thegear casting and which is adapted to bear against a suitable surface 16on,.-the casting of the rack 8. .The outline of each cam 15 correspondsto the-pitch line of the gear 7, and each surface 16 against which thecam bears, corresponds with the pitch line of the rack 8. By referenceto the figures, it will be seen that if the platform 4 is movedhorizontally, the rack 8, one on eachcorner Patented Mar. 7, 1916.

of the platform, will engage its correspond.- ing gear 7 and cause thelatter to turn. This will operate to turn the cam 15 and raise theplatform 4 on a vertical incline as the platform moves horizontally. Inthis elevating operation the parts all move with rolling friction only.Such an elevating mechanism has been described and shown in detail andclaimed in the co-pending application filed Sept. 9, 1913, by William F.l'rrgang, Serial No. 788,795. The elevating mechanism is shown here as atype of elevating which may be used in combination with my improvedparts to be described. The invention, broadly, is not limited to anyspecific type of elevating means to cause the platform to be raisedvertically when the platform is moved horizontally,

as many other types'might be used in the combinations of parts asclaimed, without departing from the scop of the invention.

The invention herein relates particularly to the mechanism for moving.the platform horizontally. The mechanism for this'purpose comprises acable 20 (see Fig. 3) preferably made of steel wires. An angle bracket21 isfastened rigidly to a cross brace of the platform 4, preferably atthe middle of said cross brace, as indicated in Figs. 2 and 3. Theoutwardly extending arm of this bracket is provided on its lower surfacewith teeth to engage corresponding teeth in a pivoted arm 22. This arm22 has a longitudinal slot provided therein and a bolt is adapted topass through a hole in the outer end of the bracket 21 and through theslot in the arm 22. A nut on the bolt engages the edges of the slot. Inthis manner the arm 22 may be adjusted longitudinally with respect tothe bracket 21 and any slack or adjustment in the cable 20 may be takenup conveniently. The arm 22 is pivoted to a holding device 23. Thisholding device 23 is made up of an open ended cone shaped piece, intothe small end of which the cable 20 is passed. The end of the cable isthen unraveled and molten lead is poured on the unraveled end of thesteel wires to enlarge the end of the cable. With this construction,referring to Fig. 3, the cable 20 will not under-any circumstances pullout of the holding .device 23. A holding device 24 similar to device 23is provided at the other end of the cable 20, as shown in Fig. 3 and thesame kind of a connection is made with the device 24 and the cable 20 asalready described. The cable 20 passes between the depending prongs of afork shaped guiding means 25 (see Fig. 3). This guiding means isfastened to a cross brace o the platform 4 and prevents lateral movementof the cable 20. At the middle of the front cross piece of the platform4, there is provided a bell shaped opening throughwhich the cable 20passes. This bell shaped opening is preferably open at the bottom,having depending prongs corresponding to the guiding device 25. By thisstructure the cable 20 is free to move vertically as long as it extendsunder the platform 4 but it is not free while under platform 4, to swinglaterally. By providing bell shaped opening 26 at the front of theplatform the cable through which a pin 6 is adapted to pass to makeconnection between the holding device 24 and the handle 1. The handle 1of the truck is pivoted immediately above the swiveled front wheel ofthe truck at the point 2, as shown. The lower end of this handle asshown comprises an inverted T- shaped casting at one corner of whichpivotal connection is made to the truck as at 2, and at the other cornerof which a horizontally pivoted rod 27 is mounted. The wheel is swiveledto the truck by means of a suitable casting having depending ears toreceive the wheel, which-casting is mounted in the main frame 4 by abearing equivalent to a' fifth wheel device. The horizontally pivotedrod 27 is held in place between two ears of the casting by means ofpivot pins 5. The rod 27, shown in Figs. 2 and 3 may always rock or turnon its horizontal pivot pins 5 with respect to the handle casting butmust in all other respects move therewith. The pin 6 passing through theholding device 24 pivots device 24 to the rod 27 which in turn ispivoted as described. The holding device 24, by means of pin 6, is,therefore, free to be moved laterally, and by means of the rod 27 towhich the pin 6 is connected, is free to swing vertically. Therefore,the device 24 holding the outer end of the cable 20, is in effectconnected to the handle 1 by means of a universal joint.

Referring to Fig. 3, it will be seen that if the handle is swungcounter-clockwise on the pivot 2, the cable will be drawn to the leftand thus move the platform 4 to the left for the elevating operation.The handle which is connected with the cable 20 as described, operateswith a bell-crank leverage to move the platform 4, forwardly. After theplatform has been moved sufliciently to elevate it to the desired pointit is desirable to lock the platform in elevated position so that thehandle 1 may be used to draw or steer the truck without interfering withthe elevating mechanism and this is done without the necessity forconnecting or disconnecting the cable 20 with the handle at eachcomplete elevating and lowering operation. At the corners of the frontcross piece of the platform 4, two

7 ends of these arms 30, as shown in Fig. 5, are

provided with shoulders or hook shaped portions to engage, each on-averticaLabutmenton one of the castings 31, fastened at each side to themain frame. These castings may be cast or otherwise connected to frame3', as by the threaded bolts shown in Fig. .1. Since the arms 30 arepivoted at .their inner ends, their own weight will cause them to dropwhenever possible. An inclined cam surface 60 (see Fig. 4) is providedon each casting 31 on which the arms 30 ride until they arrivevertically above the abutment before mentioned. A flange 31 is providedfor each cam surface to cooperate with the side face of the main frame 4to make a recessed path for the arms 30 as they move to locked,position. The platform is now in the desired elevated position and thehooks at the outer ends of arms 30 drop into position to engage thevertical abutments before mentioned on castings 31, and prevent theplatform which, in this position is designed to carry a heavy load, frombeing lowered. In this operation the handle is lowered to the positionindicated in Fig. 3. With the platform thus locked, the handle 1 may beraised to draw the truck and steer it as desired. When the platform israised and the handle is raised, the weight of the pivoted holdingdevice 23 and the cable 20 causes the latter to sag vertically betweenthe guiding members 25 and the sides of the bell shaped opening 26. Thecable is thus kept ready for use but entirely out of the a way, with nopossibility of it swinging laterally under the truck to contact with anyof the other flparts of the truck or with objects on the cor.

I When it is desired to release the lock, the handle 1 is lowered andthe platform 4 is pulled forwardly a slight amount until the hooks atthe ends of members 30 engage a shoulder on the upper end of the pivotedlatch 34. This latch-is pivoted as shown in Fig. 4, to swing in a slotin the casting and normally occupy the full line position. The handle 1is raised and the pivoted device 34 as. it turns on its pivot causes thehook portion of the lock 30 to ride over the vertical abutment on theend of casting 31, without engaging therewith, and onto the cam surface60. The latch 34 in this operation moves to the dotted line position inFig. 4, but after the hook 30 is delivered to the surface 60 the latchreturns by gravity to its full line position. The platform is lowered tothe position shown in Fig. 1 by gravity as soon as the lock is released.

' The handle 1, which is in the lowering operation held by theoperator-to brake the on the platform. For this contingency adevice isprovided to automatically lock the platform in elevated position or inpractically thesame position in which the plat-' form is when the handleis accidentally or carelessly released. This locking device is bestshown in Figs. 1 and 3. It comprises a casting 41 fastened to the mainframe of the truck and having provided therein as shown, an inclinedslot, the upper surface of which is provided with teeth 42 and the lowersurface of which is provided with uniform rolls 43. A lever 40is-pivoted to a cross brace of the platform 4.and has at its lower end adownwardly extending pivoted dog 44. This dog is so shaped and pivoted,as indicated in Fig. 4, that if the platform 4 is lowered at a certainspeed, the dog will remain out of engagement with the teeth 42 but will,as the lever 40 is lowered, ride up and down over the rolling surface 43without engaging the teeth 42. If, however, platform 4 starts to dropquickly, the dog 44 in riding over the rolls 43 on the lower surface ofthe slot, will engage one of the rolls 43 with such force as to bethrown upwardly and the dog will thus engage one of the teeth 42. Theseteeth are so shaped that they will hold the dog therein as soon as itengages in one of them. This holding operation is aided by the fact thatthe weight of the platform forces the single tooth of the dog into theengaged tooth of the teeth 42. The platform will thus be automaticallylocked in elevated position almost immediately after the handle isreleased. In order to lower the platform from this position it isnecessary for the operator to 7 take hold of the handle 1 and pulltheplatform forwardly, and thus the lever 40 and dog 44, enough to allowthe dog 44 to drop from its engagement with one of the teeth 42. Theplatform may then be lowered provided the speed is not increased beyondthe degree predetermined by the construction of the safety device.

I am aware that cushioning devices have heretofore been used with lockreleasing means in elevating trucks to control the speed of theplatforms descent. An automatically operated locking device having thefunction of the one here shown I believe to be broadly new. In thisapplication such a device is claimed in combination with the otherimproved features of my truck. In U. S. Letters Patent #1,102,871,granted to me July 7, 1914, I claim the device broadly, and in othercombinations.

I have shown in combination with the ele vating mechanism heretoforedescribed, a convenient means for preventing the platform from tipping,due to unevenly placed loads thereon. This means includes at each cornerof the truck, a depending flange 50 (see Fig. 6), which flange isintegral with the casting of the rack 8. An inclined slot 51 is providedat the lower corner of this flange, having its lower end closed and itsupper end open. A pin 52 integral with the casting of the gear 7 isadapted to enter slot 51 as the gear is turned and the rack 8 and theflange 50 move in an incline upwardly. Another flange 9 is integral withthe casting of the rack 8 and is constructed to extend verticallydownwardly and then horizontally below the hub of the gear 7. The flange9 is so shaped that as platform 4 moves upwardly, one edge of the flange9 will be in continual engagement with the lower part of the hub of thegear 7 and thus be in effect a hook which will prevent the platform fromtipping. Since there are 4 of these hold down hooks, one at each cornerof the platform, the latter can not tip or lift off the main frame 3.The platform moves on an incline upwardly to such an extent that theflange 9 finally leaves its engagement with the said hub but at, or alittle before this time, the pin 52 enters the slot 51 and by means ofthe flange 50, the pin 52 thereafter prevents any tilting of theplatform. If the hook endsof flanges 9 were long enough to hold theplatform down at all times, the lower ends of the flanges would not, inthe structure shown, clear the floor as much as desired. For this reasonthe flange 50 and pin 52 are provided to cooperate with flange 9.

While I have shown and described one preferred embodiment for thepurpose of illustrating the manner in which it may be carried out, I donot desire to limit my invention to the one form shown and thereforehave broadly claimed certain features and combinations of the invention.

What I claim is: v

1. A truck comprising a wheel supported platform, a handle connected toone of the wheels for steering the truck, means to elevate the platformwith respect to the wheels, and a universal jointed connection betweensaid means and handle.

2. An elevating truck comprising a frame and a superimposed platform,means to convert a horizontal movement of the platform into a verticalmovement with respect to the frame, a steering wheel, a handle pivotallyconnected therewith, a flexible cable connected to the handle with auniversal joint at a distance from its pivot point and connected to theunderside of the platform at a distance from its front edge, allconstructed and arranged so that the platform may be lifted with respectto the frame when the handle is swung downwardly on its pivot.

3. An elevating truck comprising a frame supported on wheels, aplatform, a handle pivoted to one of the steering wheels to steer thetruck, means to elevate the platform from the frame, a cable having apivoted connection with the handle for lateral and vertical swingingmovements and connected to operate said elevating means by move 'ment ofthe handle, a lock independent of the elevating means, constructed tohold the platform in elevated position, and means to automaticallyrelease said lock, operable by movement of the handle.

4. A truck comprising a wheel supported frame, a platform thereon, ahandle pivoted to one of the wheels for steering the truck, means toelevate the platform from the frame, a cable connected to the handle ata distance from its pivot with a universal joint and connected tooperate said elevating means by movement of the handle, a lock to holdthe platform in elevated position, said lock constructed to operate tolock whenever the handle is lowered to a predetermined point, and meansoperable to automatically release said lock when the handle is loweredto another predetermined point and then raised.

5. A truck, comprising, a wheel supported frame, a platform mountedthereon, a handle pivoted to one of the wheels for steering the truck,means to elevate the platform from the frame, said means being operableby a device connected at all times with the handle and platform, anautomatically releasable lock operable by the handle, all constructedand arranged so that a downward movement of the handle to apredetermined pointwill lock the platform in elevated position, and afurther downward movement of the handle will operate the lock to releasethe same when the handle is raised to an elevated position, whereby theplatform may be raised and locked in elevated position by one downwardsweep of the handle and may be automatically released and lowered by acombined downward and upward sweep of the handle.

6. A truck comprisirfg a wheel supported frame, a platform thereon, ahandle pivoted to one of the steering wheels to steer the truck, meansoperable to elevate the platform from the frame, a cable connectionbetween the handle and the platform arranged to operate said elevatingmeans, said cable connected to the handle at all times, an automaticallyoperable lock constructed to hold the platform in elevated position whenthe handle is lowered to a predetermined point, said cable beingconnected to the handle by a universal joint, whereby the handle mayOperate to elevate the platform and lock it in elevated positionwhenever lowered while turned horizontally at any angle to the lonplatform mounted thereon, means operable from the handle to elevate theplatform from the frame by longitudinal movement of the former, ahook-shaped locking device pivoted to the platform, a member on theframe formed with an inclined portion to guide said locking deviceupwardly as the platform 15 elevated and a shoulder engageable by saidlocking device when the platform has been lifted to a predeterminedposition, and a pivoted dog within said member engageable by the lockingdevice on continued upward movement of the plat- 10 form, said dogarranged to be moved by the locking device as the platform is lowered tocarry the locking device over said shoulder,

whereby the platform may be automatically locked in its lifted positionand released for lowering by manipulation of the steering 15

